Well, if you're trying to keep shutter speed high, I can see the need for that. I've shot plenty of wedding receptions that are painfully dark though - and the majority of the time, the best answer is just off-camera flash, or bounce flash if the situation is right. I'm mainly saying that because a lot of times the camera is physically capable of focusing and I could, in-principle, crank up the ISO and shoot without extra lighting, but in situations like that your colors are so muted and there's so little dynamic range in the lighting environment that the pictures that come out are flat and drab, or schizophrenic and nonsensical depending on the DJ's lighting setup.
Much better to have an off-camera flash or two, slow that shutter down enough to get a hint of motion blur and ambient lighting, but rely on the flash to keep the subject nice and sharp. Some of those scenarios really have been so dark though that I can't actually see well enough to compose a shot very well (I can tell that people are dancing, but can't see expressions, etc) so it really is a "shot in the dark". Thankfully, I still often manage to get some fun expressions and positions.
Everybody has their own style, but for myself I find that all my favorite dark reception hall shots are made with a setup along those lines - and honestly, the wide aperture is more of a hazard than a benefit so I find myself at 4.0 as often as not, because things are moving so fast that getting a razor-thin DOF dialed in exactly where you want it is next to impossible. The off-camera lighting provides the drama and subject isolation that you usually rely on bokeh for.